The invention relates to an improvement in temperature compensated voltage reference circuits. U.S. Pat. No. 3,617,859 issued to Robert C. Dobkin and Robert J. Widlar on a basic voltage reference circuit and is incorporated herein by reference.
An improved form of temperature compensated voltage reference circuit is disclosed in copending application Ser. No. 888,721 filed Mar. 21, 1978, by Robert C. Dobkin and titled AN IMPROVED BANDGAP VOLTAGE REFERENCE.
In the design of electronic circuits constant voltage references are often useful. The object is to develop a potential that has an absolute known magnitude that is substantially independent of current supply and load conditions. The avalanche or zener diode is characteristic of such a device but it has a temperature responsive voltage characteristic that is established by physical parameters. Furthermore, such devices have a knee, or transition region from variable to constant voltage, that produces noise. The so-called bandgap voltage reference devices have been developed in integrated circuit (IC) form in which the fundamental electronic properties of the semiconductor material are employed to develop a reference potential.